Bridge.



No. 683,627. Patented out. 190|.

. F. s., VENT.

No. 683,627. Patented Oct, I, I90I.

F. G. VENT.

B R I D G E. (Applicatmn mea Fes'. 2, 1901.)

2 Sheets-Sheet 2.

V Av

UNITED ,STATES PATENT OFFICE."

FREDERICK G. VENT, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TOv CHARLES O. BAUGHMAN, OF SAME PLACE.

BRIDGE.

SPECIFICATION forming part of Letters Patent No. 683,627, dated October 1, 1901.

Application filed February 2, 1901. Serial No. 45,795. (No model.)

To all whom it may concern:

Be it known that I, FREDERICK G. VENT, a citizen of the United States, residing at Chicago, county of' Cook, and State of Illinois,

have invented certain new and useful Improvements in Bridges, of which the following is a specication,reference being had to the accompanying drawings,forming a part thereof.

The purpose of this invention is to provide a bridge structure especially adapted for use in a bascule or lift bridge consisting of two members swung upon opposite piers and designed to open at the middle and to be opened by swinging upon their respective supports and which when closed together shall act as a single rigid span imposing upon their respective supports at the opposite ends direct vertical loads only.

Heretofore bascule or lift bridges which 2o part in the middle have been constructed upon one of two plans-to wit, either so that they meet and bear against each other at a point sufficiently above their pivotal or rolling supports to cause them to operate as an arch construction or so that they meet substantially in the horizontal plane of their pivotal or rocking support, each member operating as a ca ntaliver, the tail or counterbalancing end being positively stopped at the proper 3o position, the structure operating as such stop, thus requiring anchorage sufficient to resist the stress of any load which may be carried upon the overhung end of the bridge member. The rst or arch construction imposes oblique loads or stress upon the foundations, causing them to settle unevenly and become distorted in shape. The cantaliver construction, necessitating the use of the tail and anchors on the short arms of the cantaliver, produces -4o two oppositely-acting stresses at different when they meet operate as a rigid span, which will impose a directly vertical load only upon each support.

It consists in certain construction ofthe meeting ends of the bridge members, as genericall y and specifically set out in the claims.

In the drawings, Figure 1 is a side elevation of a bascule-bridge embodying my invention. Fig. 2 is a detail top plan of the 6o middle of the bridge or meeting portion of the two members. Fig. 3 is a detail section, on an enlarged scale, at the line 3 3 on Fig. 2. Fig. 4 is a similar detail section at the line 4.4 on Fig. 2,/ Fig. 5 is a detail top plan of the 65 structure shown in Fig. 3. Fig. 6 is a detail elevation of part of what is shown in Fig. 4. Fig. '7 is a detail plan of the middle portion of the bridge, having a slightly-modified construction. Fig. Sis a side elevation of a por- 7o tion of a bridge structure, shown in outline without minor details, in which my invention is applied to a bridge made in more than two sections.

A A are the two members of a basculebridge, pivoted at c a upon their respective piers B B. The general construction of the bridge members need not be detailed. I have shown a trussed construction throughout, though my invention is not limited to such 8o construction. The portions of the structure embodying the details of my invention comprise only the terminal triangle of trusses of the members, respectively, and these will be described. The terminal triangleof each side 8 5 element of each member of the bridge comprises the upper chord, the diagonal extending from the end of such chord obliquely back downward to the lower chord and the post extending from the foot of such diagonal di- 9o rectly to the upper chord. The lower chord if extended beyond the foot of the post is so extended merely for the purpose of carrying a floor, but is not essential to the operation of my invention. The structure of these termiual triangles of the two members is somewhat different, and their several parts will be indicated by distinctive letters. I have shown the upper chord of each member as consisting of vertical channel-beams, back 10o toward back, suitably spaced and braced apart throughout the remainder of the extent of the bridge member, except the terminal portion, constituting the horizontal leg of the terminal triangle. In the right-hand member of the bridge the terminal portions M M of these channel-beams of the upper chord are shown extended beyond the post without the intervening braces or other connection. The corresponding portions N N of the channel-beams of the left-hand member are beyond the post offset inwardly, so that they may pass between the terminals M M of the chord of the opposite member. These terminals N N may be suitably spaced and secured together so as to be as rigid as possible throughout the portion which is thus adapted to enterbetween the terminals M M, and the terminals M M may be connected at their extremities by a plate lm, spanning the interval between them at the upper side. The usual gusset-plates M2 are employed and bent outwardly in the upper end to form guides M20 for the end of the opposite chord as it approaches its seat on the top of the post, whose channel elements M' M'are terminated enough below the level of the lower edge ofthe chord channel-beams M to allow room for a capplate M3. Stidening-brackets or angle-plates M4 are added on the outside of the gussetplate, having their vertical iianges riveted through to the web of the plate and the postchannel and their horizontal lianges riveted to the anges of the chord channel-beam. The channel elements of the post N' of the left-hand member are set directly underneath the channel-beams N N of the chord of that member and are secured by gusset-plates N2 inside against the webs ot both channels, and cross-plates N3 N3 are riveted to the iianges of the post-channels, being placed with their upper edges abutting under the lower edges of the chord channel-beams N, such plates projecting laterally outside the posts to aiord lodgment for the channelbeams M M of the chord of the right-hand member. In order to increase the surface for suchlodgment, inverted channel-pieces N4 N4 are inserted between the parallel projecting portions of the plates N3 and riveted by their iianges to said plates, with the upper surface of the web of such channel-piece flush with the edges of the plate. It will be understood that the diagonals M5 and N5 of the two members are secured to the chords, respectively, far enough back of the ends of said chords to leave said ends free to make the lodgment described in the seats provided on the posts of the opposite members, respectively.

When it is desired to have the tloor of the bridge located on the lower chords M6 and N6 of the members, respectively, they may be projected toward each other beyond the posts M and N to afford support for the floor through the extent of the lapping portion of the members. Such extensions of the lower chord may be supported by tie-rods M7 N 7, as illustrated.

Instead of constructing the upper chord of the two members in the manner above described-that is, so that one of them is bifurcated and the other enters such bifurcation to prevent lateral displacement-the same result may be secured by arranging the opposite side elements ot' the members, respectively, so that said side elements of one member pass between the corresponding side elements of the other member, one member having both its side elements outside and the other member having both its side elements inside. Such construction is illustrated in Fig. 7, in which Ma Ma are upper chords of the side element of the right-hand member and Na Na the upper chords of the correspond` ing elements of the left-hand member, vthe opposite members being tied together by transverse bars lidb and N", respectively, of which the latter project beyond the chords M and N, affording stops for the lodgment of the ends of the chords M and Mb, while the chords Na and Nb are similarly stopped by lodging on the bar Mb, immediately inside the chord N, respectively. The details of the structure will of course be somewhat modified in this construction; but the necessary modifications will be obvious to any mechanic without specific explanation.

It will be evident that this invention is not limited in its use to bascule or lift bridges, but that it may be employed merely for the purpose of making iixcd bridges in sections, which when joined in the manner indicated will constitute a rigid span. This may be done for the purpose of making the separate parts small enough so that they can be shipped fully constructed to the point where they are to be erected or for any other sufcient reason.

The same expedient or features ofconstruction may be employed to connect together successive elements of a bridge-span whatever the numberthat is, it is not limited to the construction of spans comprising two members only. In Fig. 8 I have shown in outline sufficiently to indicate in a general way the method of construction of a three-part span, of which the middle part is joined to each of the others in the manner described. In this case I have shown the two outer portions X X ot the span with their upper chords constructed similar to the right-hand member of the bascule-bridge shown in the principal iigures and have shown the middle section Y with both ends constructed like the terminal of the left-hand member in the principal tigures.

Although I have shown the interlocking and stopping of the two members upon each other in the truss-bridge as effected by such interlocking'and stopping of the upper chord, I do not limit myself to the use ot' the upper chord for this purpose; but there is a specific advantage of the construction which permits the use of the upper chord in that-the lower chord may be omitted, and thereby greater IIO height of waterway may be Yobtained under the bridge for the distance of the interlap of the two portions. This will frequently make it unnecessary to lift the bridge in order to allow a small vessel to pass, such as a tug or small steamer whose smoke-stack is the highest part for which provision must be made, such smoke-stack finding accommodation in the space left by omitting the lower chord. When the floor of the bridge is mounted on the lower chord, the extension of the two members across the interlapped portions and the door portion mounted on such extensions may be arranged to be swung up to open a passage for the smoke-stack on the tug or steamer, and thus avoid the necessity for swinging up the entire bridge. Any suitable means may be provided for sustaining the outer ends of these extended chords and floorsections and for raising and lowering them, as cables WV W, running over suitable guides overhead and operated by any suitable motor or by a hand-windlass.

I claiml. A bridge-span, comprising a plurality of longitudinallysuccessive sections or members connected together, of which the extreme sections are supported at their remote ends, and the intermediately-conne'cted ends are lapped by each other and vertically stopped on each other at their lapped portions at longitudinally-separated points; the upper element at each of said points being the one whose extremity is nearer said point.

.2. A bridge, having two members supported at their opposite extremities and lapping by each other at their proximate extremities, said members being vertically stopped against each other at their lapped portions at two longitudinally-separated points, the upper member at each of said points being the one whose extremity is nearer said point.

3. A double bascule-bridge, having its two .members adapted to lap by each other as they close together, said members being vertically stopped against each other at their lapped portions at two longitudinally separated points, the upper member at each of said points being the one whose extremity is nearer said point.

4. A bridge, composed of two trussed members supported at their remote extremities and each terminating at their proximate extremities in an underbraced upper chord,such chords -lapping by each other and vertically stopped against each other at their lapped portions at two longitudinally separated points; the upper chord at each of said points being the one whose extremity is nearer said point.

5. A double bascule-bridge, composed of two trussed members each terminating in an underbraced upper chord, such chords when the members are closed together lapping by each other, and being vertically stopped against each other at their lapped portions at two longitudinally-separated points, the upper chord at each of said points being the one whose extremity is nearer said point.

6. A bridge, composed of two trussed members, supported at their remote extremities,

and at their proximate extremities terminating each in an underbraced upper chord,such chords lapping by each other substantially to the strut of the truss-triangles to which the chords respectively pertain, and being each lodged and stopped on the upper end of the strut of the other member.

A 7. A double bascule-bridge, composed of two trussed members, each terminating in an underbraced upper chord, such chords when the members are closed together lapping by each other substantially to the strut of the truss-tria-ngles to which the chords respectively pertain, such chords when the members are closed together being lodged and stopped each on the upper end of the strut of the other member.

8. Abridge, composed of two members,each supported at their remote extremities and having their corresponding sides lapping by each other at their proximate extremities, such lapped side elements being vertically stopped against each other at their lapped portions at two longitudinally-separated points, the upper element at each of said points being the one whose extremity is nearer said point; the two side elements of one member being arranged to lap outside the side elements of the other member.

9. Adouble basculebridge,whose two members are each supported at their remote extremities and whose corresponding side elements lap by each other as the members close together, said elements being vertically stopped against each other at their lapped portions at two longitudinally-separated points, the upper element at each of said points being the one whose .extremity is nearer said point, the two side elements of one member being arranged to lap outside the respectivelycorresponding side elements of the other member.

10. A bridge, composed of two members which are each supported at their remote extremities, and at their proximate extremities lap by each other and are vertically stopped against each other at their lapped portions at two longitudinally-separated points; the upper member at each of said points being the one whose extremity is nearer said point; one

IOO

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of said members having its lapped portion biresponding ehord of the other member being interlapped with such bifurcation.

12. A double bascule-bridge, composed of two trussed members, each terminating in an underbraced upper chord and arranged when closed together to lap by each other, and being vertically stopped against each other at their interlapped portions at two longitudinally-separated points, the upper chord at each of said points being the one whose extremity is nearer said point; the lower chords of the two members being extended toward.

each other under the interlapped extent of the upper chord, to aiord Hoor-support at such interlapped part.

In testimony whereof I have hereunto set my hand, at Chicago, Illinois, this 26th day of January, A. D. 1901, in the presence of two witnesses.

FREDERICK G. VENT. In presence of- CHAS. O. BAUGHMAN, CHAS. S. BURTON. 

